Arrangement on talking apparatus for the reception and reproduction of records



Dec. l5` 1925- 1,565,968

K. H. SMITH ARRANGEMENT ON TALKING APPARATUS FOR THE RECEPTION AND REPRCDUCTON OF RECORDS Filed June 16, 1921 Patented Dem-15, 1925.

UNITED STTES PATENT OFFICE.

I `KRISTIAN HARALD SMITH, 0F COPENHAGEN, DENMARK.

ARRANGEMENT oN TALKING APPARATUS FOR THEl RECEPTION AND REPRODUCTION i or RECORDS.

Application led June 16, 1921. Serial No. 478,135.

To all wiz/0m 'it may concern.'

Be it known that I, KRISTIAN HARALD SMITH, a subject of the King of Denmark, residing at Copenhagen, Denmark, have 1nvented certa-in new and useful Improvements in an Arrangement on` Talking Apparatus for the Reception and Reproduction ot Records, of which the following is a specification.

This invention relates to a device which is designed to transfer the vibrations of mechanically operated diaphragms, e.. g. of phonograph cylinders, gramophone disks or the like, to other diaphragms which are controlled by magnets.

The invention -consists essentially in this,

that the mechanically operated diaphragm transfers its vibrations to a second diaphragm. For this purpose the air enclosed in the head of the talking machine can be utilized besides mechanical means for transmission. Magnets are arranged behind the second diaphragm whose vibrations generate feeble currents in the windings of these mag- .nets These feeble currents are then transferred to another magnet which on its part makes another diaphra m vibrate.

The vibrations of this latter diaphragm are therefore caused merely by the variation of the intensity of current in the magnets due to the vibrations of the first mentioned diaphragm, that is to say without the aid of any mechanical means. No battery needs to be inserted in the circuit. Very clear tones are consequently produced by this diaphragm so that the conversation recorded on the phonograph cylinder or on the gramophone disk are reproduced distinctly.

The arrangement can be further made in such a manner that this electrically operated diaphragm is not mounted in the same casing as the others but at any other place, e. g. directly in the receiver head.

In order that the invention may be clearly understood, I shall proceed to describe the same with reference to the several forms given by way of example in the accompanying drawing, wherein Fig. 1 shows the diaphragms combined in one casing.

Fig. 2 illustrates the arrangement according to which the receiver diaphragm is separatedfrom the transmitting diaphragm.

Fig. 3 shows diagrammatically a connection with condensers for the clearest possible reproduction of the sounds.

The casing a of the talking head is divided into two separate parts by a partition b. At either side of the partition b an annular steel `magnet c or d respectively with polepieces g or h is arranged. Thecoils are connected to one another by spring Z and the contacts m. The diaphragms fn. and o are phragm are thus transferred toa second dial phragm which itself operates a third diaphragm by electric currents.

The apparatus described can also be used as receiver when the switches are reversed Vso that the contact at m is interrupted, the' contact at t being closed. If in this case a person speaks into the microphone u which may be arranged at any convenient point, the diaphragm a will be vibrated by the variation of intensity of current in the wire o and the diaphragm n. will transmit its vibrations to the diaphragm The reception can be madeafrom any distance. For the reproduction of the conversations recorded on the cylinder s the receivers w are used which are connectedwith the diaphragm o by a tube.

In the form'of construction shown on Fig. 2 the talking head a comprises only the diaphragms p and n. The dia-phragms o which are to be operated from diaphragm 'n by means of magnetic currents are mounted in the receivers fr. A condenser 2 can be inserted in the circuit y of the receivers. This arrangement has the advantage that noises produced by the revolving of the cylinder s and bythe driving of the same are not transferred to the receivers. Experiments have shown that a very clear and'distinct reproduction of the communication is obtained.

According to Fig. 3 two condensers 1 and 2 are inserted in the circuit.

The condenser 2 is inserted in the wire 3 between the two magnets g and it, the condensers Z being mounted in a connecting wire 4:. rl`his arrangement ensures also a clear and distinct reproduction of the communications received.

The constructionai details can. be moditied according to requirement.

The essential feature oit the invention is the transfer of the mechanically produced vibrations or1 the receiving diaphragm to the reproducing diaphragm by electricity.

l. Ilhe combination of a diaphragm, a second diaphragm, mechanical means 'for transmitting the Vibrations of said firstnamed diaphragm to said second-,named diaphragm, a magnet electro-magneticlally coacting with said second-named diaphragm, a third diaphragm, a magnet co-operating with said third-named diaphragm, an electrical circuit interconnecting said magnets, a microphone and switching means for connecting saidl microphone with said tirstnamed magnet while disconnecting said Hirst-named magnet out of circuit with said second-named magnet.

2. The combination of a reproducing diaphragm, a second diaphragm, mechanical means interconnecting said first-named and said second-named diaphragme to transmit vibrations from one to the other, a magnet inmagnetic relation with said second-named diaphragm, a third diaphragm, electro-magnetic means controlling said third-named diaphragm and an electrical circuit interconnecting said magnet and said. electroneeaeee to transmit the Vibrations of one to the other, a magnet in electro-magnetic relation with said second-named diaphragm, a third diaphragm, a magnet contro-lling the vibra tions of said third diaphragm, an electrical circuit interconnecting said first-named and said second-named magnets, a microphone connected to said electrical circuit and switching means tor interconnecting said microphone in circuit with said irst-named magnet.

le The combination of a reproducing diaphragm, a second diaphragm, mechanical means interconnecting said irst-named diaphragm and said second-named diaphragm to transmit the vibrations of one to the other, a magnet in electro-magnetic relation with said second-named diaphragm, a third diaphragm, a magnet controlling the vibrations oic said third diaphragm, an electrical circuit including a condenser interconnecting said first-named magnet and said secondnamed magnet, a microphone and switching means for connecting said microphone with said tiret-named magnet while disconnecting said first-named magnet out of circuit with said second-named magnet.

ln testimony whereof ax my signature.

nnrsrran HARALD sii/nan. 

